Terremark, like any Internet exchange, is vital to the network. That's why the walls are made of seven-inch, steel-reinforced concrete that can withstand the 155mph winds of a Category 5 hurricane. That's why environmental control is fanatically precise, keeping condensation off the circuits and the thousands of servers cool. That's why on top of paying $630,000 a month for electricity, the building also maintains its own bank of diesel generators as a backup. And that's why, if any disaster were to strike Miami, restoring Terremark's power would have priority along with hospitals and the police. In short, it would be very bad if something happened at Terremark. "If a service provider goes down, it's terrible," says Derrick Cardenas, Terremark's regional vice president of commercial sales. "If we go down, it's global."